The Splash Tetra is a small, slender fish with a standard length of 3 to 4 cm. The mouth is relatively large and upturned, with acutely pointed teeth; this contrasts with the more horizontal mouth of the rather similar pencil fishes (Nannostomus). The maxillary bones are curved in an S-shape and the nostrils are separated by a ridge of skin. There is a dark spot on the dorsal fin and a dark line from the snout to the eye, which may continue to the operculum. There is no lateral line and no adipose fin.
The species is endemic to tropical river basins in South America where it is present in river systems from the Orinoco to the Amazon River. It is found in shallow streams, both in clearwater forest creeks and in blackwater creeks in swamps and wetlands.
Worms, crustaceans and other invertebrates, particularly small insects that fall onto the surface of the water, make up the splash tetra’s diet.
This fish has an unusual system of reproduction, with the male fish caring for the eggs. During the breeding season, the male chooses a suitable location with overhanging foliage. When he has attracted a female to this spot, the pair simultaneously leap out of the water and cling onto a low-hanging leaf with their pelvic fins for up to ten seconds. Here the female lays a batch of six to ten eggs which are immediately fertilised by the male before both fish fall back into the water. Further batches are laid in a similar manner until there are 100 to 200 eggs on the leaf and the female is spent. The male remains close at hand, repeatedly splashing water onto the eggs to keep them damp. The rate of splashing is up to about 38 splashes per hour. The eggs hatch after some 36 to 72 hours and the fish fry fall into the water below.
Best kept in a densely planted aquarium or paludarium with some overhanging vegetation, roots or branches important if you wish to raise fry alongside the adults. Floating vegetation is also useful since this species appears to prefer relatively dim conditions and spends much of its time in the upper part of the water column.
The addition of dried leaf litter further emphasises the natural feel and as well as offering additional cover for the fish brings with it the growth of microbe colonies as decomposition occurs. These can provide a valuable secondary food source for fry and the tannins and other chemicals released by the decaying leaves are also considered beneficial for fishes from blackwater environments. Alder cones may also be used for the latter purpose.
The water should be well-oxygenated with a little surface agitation advisable. Do not add this fish to a biologically immature aquarium as it can be susceptible to swings in water chemistry.
It’s perhaps best-maintained alongside similarly-sized characids, gasteropelecids, lebiasinids, smaller callichthyid or loricariid catfishes and diminutive, non-predatory cichlids.
Try to buy a mixed-sex group of at least 8-10 specimens, include other schooling fishes to provide security, and you’ll be rewarded with a more natural-looking spectacle. Males will also display their best colours and some fascinating behaviour as they compete with one other for female attention.